Grinding machine



Oct. 10, 1944.

W. L. CARSON GRINDING MACHINE 4 Sheets-Sheet 1 Filed June 29, 1942INVENTOR ATTORNEY Oct. 10, 1944. w CAVRSQN 2,359,969

GRINDING MACHINE Filed June 29, 1942 4 SheetS -Sheet s I E I ATTOR/VEYOct. 10, 1944. w. L CARSON GRINDING MACHINE 4 Sheets-Sheet 4 Filed June29 1942 Patented Oct. 10, 1944 GRINDING MACHINE William L. Carson,Seattle, Wash, assignor 'to Washington Iron Works, Seattle, Wash., acorporation of Washington Application June 29, 1942, Serial No. 449,035

16 Claims.

This invention relates to radial grinding machines, and for itsobjectaims to provide an extremely eflicient machine forprecision-grinding concentric surfaces and one, more especially,

which is self-feeding for imparting a predetermined and selectivelyvariable axial advance to the grinding tool at cyclic intervals.

It'is a further object of the invention to provide a radial grindingmachine embodying devices performinga stop function automaticallylimiting the cyclic feed movement to a predeter- -mined maximum-of axialtravel.

With the foregoing and still further objects and advantages in view, theinvention consists chine embodying my improvements and having partsshown fragrnentarily and other parts broken away and shown in horizontalsection.

Fig. 2 is aside elevational view thereof shown partly in longitudinalvertical section and delet-- ing the drive motor and the double-rackgear which function to impart a reciprocatory swinging movement to thetool-carrying beam.

Fig. 3 is a fragmentary horizontal section on line 33' of Fig. 2. r

Fig. 4 is a view in elevation of the end proper of the swinging beam andits supported tool.

Fig. 5 is a viewtaken to an. enlarged scale and illustrating, in topplan, the shear-pin assembly employed to drive-couple the swinging beamto a drive bracket driven from the double-rack gear. I

Fig. 6' is a verticalsectional view on line 6-6 of Fig. 5.

Fig. 7 15a fragmentary longitudinal vertical section to-an enlargedscale detailing the transmission mechanism which operates to impart acyclic feed to the grinding tool.

Figs. 8 and 9 are transverse vertical sections on the respective sectionlines 8-8 and 95 of Fig. '7; and

Fig. 10 is a fragmentary end view taken to an enlarged scale andirom adirection opposite to that-of Fig. 8 to further detail the lost-motiondrive which characterizes my feed mechanism, the parts being shown inpositions different from that of Fig. 8.

In said drawings, the numeral llindicates the swinging beam of mymachine, and I2 a pedestal ;post upon which the same is journaled andwhich is rigidly bolted to a bed plate l3, the bed plate also acting asa footing for a clamped work-piece which I have designated by the letterW. Formed upon the top and bottom of the beam to extend along a sideedge thereof are-a rail l4 and a complementing flared tongue l5, andtracking thereon for movement longitudinally of the beam is a carriage[6. Received in a side channel of the beam and held against end movementin bearing blocks |'I--l8 is a feed-screw 20, and working on the screwis a walking nut 2| secured tothe carriage. A controlling crank handlefor the screw is indicated at 22.

Said carriage, upon its outer face, provides a pair of spaced apartvertical ribs l6 which act in complement to describe a dove-tail tongue.Formed with a correspondingly shaped grove to slidably workupon thistongue, there is provided a plate 23 which carries a stud bolt 24 fittedwith a locking nut25, and mounted thereon is a grinding head 26 tiltablyadjustable about a lrorizontal axis tangential to a circle taken aboutthe center of the journal post [2 as an axis. The grinding head isself-contained, which is to say that the same mounts an electric motor21 and a tool supporting arbor, as 28, having constant-drive connectionwith the motor. 28 indicates the grinding tool.

From the foregoing, it'will be understood that the grinding head isadjustable toward and from the swinging axis of the beam by means ofthe,

longitudinal slide, and is also adjustable for leadnamely in a directionlongitudinally of the axis of the post l2by means of the vertical slide,and for accomplishing this latter function I employ a bell-crankassembly built up from separate lever arms which are keyed to a commonfulcrum pin 30 journaled transversely through the upper extension of thecarriage. -One of these lever arms, as 3|, connects by a link 32 withthe plate 23, and the other lever arm, as 33, is or may be furcate inform and connects by parallel linkage 34 with trunnionposts providedupon opposite sides of. a feed-screw nut 35. The feed-screw for this nutis designated by 36 and at its outer end finds a bearing in an extensionN5 of the carriage, the opposite or innerend being received through anautomatic intermittent-feed transmission which will be hereinafterdescribed. There is provided a crank handle 31 for manually settingthefeed-screw; and hung from an arm 38 which is or may be integral with thelever arm 33 is a counter-weight 3%.

Considering now the drive for swinging the beam in its reciprocatorymovement, the invention employs a drive bracket 40 journaled upon askirt dependency H of the beam and formed with a radial arm in which isa longitudinal slot 4|. Fixed to the bracket in adjusted relationlongitudinally of the slot, thereby to regulate the swinging arc of thebeam, is a wrist pin 42 which connects with a driving arm 43, thedriving arm having fixed to its underside a double-rack driving gear 44driven from a pinion 45, and the pinion being driven through suitablereduction gearing from an electric motor 46. Between the drive bracketand the beam is a drive coupling including a shear-pin. 41 and, to theend of adapting such pin to repeated usage, the same is given a slidefit for axial take-up in a sleeve 48. The sleeve is socketed in abearing 49, and carries a draw-pin 50. While I have indicated thisdraw-pin as serving the added end of a set-screw for the shear-pin, aseparate screw for this purpose is preferably applied in countersunkrelation to the sleeve at the lower end of the latter.

Reverting to the feed-screw and describing the intermittent-feedtransmission hereinbefore mentioned, it will be seen that a sector bevelgear 5| is rigidly clamped upon the upper end of the journal post l2,and that a hollow bevel pinion 52 is journaled in a beam-carried bearing53 to mesh therewith. Finding a revoluble mounting within the pinion andprojecting forwardly therefrom is a sleeve 54, and mounted upon theforward projection of the sleeve is a disc 55 formed with a peripherallug 55' arranged to be driven through a lost-movement drive from adriving disc 56 fixed to the pinion. This lost-movement drive iscomprised of a pair of driving dogs 5158 clamped in adjusted positionsupon the rim of the driving disc, with one of the dogs acting to engageand drive the driven lug in one direction of the pinions rotary movementand the other dog operating in the return movement of the pinion todrive the lug in the opposite direction of rotation with the lost motioncorresponding to the spacing which obtains between the driving faces ofthe two dogs. From the driven disc the drive is carried through areversible pawl 60 to the teeth of a ratchet gear 5| which, like thedriven disc, is freely revoluble upon the sleeve 54. Indicated .by 64 isa leaf spring functional to the pawl for yieldingly depressing theselected pallet 60' or 60", as the case may be, into operative drivingrelation to the ratchet gear. This said ratchet gear is produced as anintegral part of the driving element of a jaw-clutch assembly includinga driven element 62, and characterizing this driven element is the factof the same being produced as a split bronze ring fitted with atightening screw 63 for adjustably drawing the same down upon a collar65 for obtaining a friction drive between the clutch and the collar, thecollar being keyed as at 66 to the sleeve 54. The feed-screw 31 isreceived through and driven by the sleeve while being permitted relativesliding movement to compensate for radial adjustment of the grindinghead. While not illustrated, the free end of the spring 64 has itsunderside transversely notched at a point which, by engagement with thepeaked back of the pawl, holds the latter in neutral position permittingthe operator to manually set the grinding tool at the desired initiatingpoint of a grinding operation by the use of the crank handle 31.

It is believed to be readily understood that the described frictiondrive from the bronze ring $2 to the collar 65 permits the former toslip upon the latter in the event of there being developedin the courseof the tool feed-a resistance of suiiicient intensity to overcome thedraw adjustment of the screw 63, and I utilize such slippage as a meansfor controlling the maximum travel of the grinding tool in its cyclicfeeding movements. To this end I fixedly mount a vertical screw 57 uponthe slide plate 23, and provide thereon a pair of knurled adjusting nuts68- 38 to have the latter lie at opposite sides of and be brought byvertical movement of the grinding tool into engagement with a stop lug10, the stop lug being fixed to the carriage [6.

The operation of the automatic feed may be explained as follows: Theoperator determines the lead desired in a cycle of the beamsreciprocatory swinging movement, and clamps the driving dogs 5!-58 uponthe rim of the driving disc 56 in correspondence therewith. There is ofcourse interdependence between the location of the driving dogs and theswinging arc of the beam from the fact that the degree to which the beamis caused to swing by the setting of the wrist pin 42 in relation to thelongitudinal slot 4i governs the number of teeth of the sector gearmeshed by the pinion 52, and by such token the portion of a turn whichis given to the pinion. The selected pallet of the reversible pawl 60 isbrought into engagement with the ratchetgear 6|, according as to whetherthe work feed is to move upwardly or downwardly over the precisionsurface of the work-piece, and the related adjusting nut 68 or 68', asthe case may be, is threaded into such position upon the fixed screw 6'!as to be brought into engagement with the stop lug 10 upon completion ofthe desired feed movements. The motors 21 and 46 are then energized,whereupon the revolving tool is caused to swing in reciprocatory travelover the precision surface of the work-piece, the pinion 52 impartinglost-motion responsive movement through the. driving dogs of the drivingdisc 56 to the pick-up lug of the driven disc which acts in turn toimpart unidirectional rotary movement through thepawl-ratchet-clutchfriction drive elements 60-6|-6265 to the feed-screw31 which, through the nut 35, connecting linkage 34, bell-crank lever3I-33, and link 32, slides the grinding head verticallythe movementbeing intermittent and occurring in each like directional swing of thebeam. The manner in which the feed movements are caused to progress onlyto a predetermined maximum or limit of travel with a resulting slippageof the friction-drive ring upon the collar as the related nut68 or 68isbrought into engagement with the stop lug 10 is thought to be clear,

It is believed to be self-evident that the functional teachings of theinvention lend themselves to operations other than grinding, and it istherefore intended that the term grinding as used in the description andclaims will be construed as including other applicable operationsexcepting in such instances as the express language describing partspeculiar to a grinding tool permits of no other interpretation.Departures from the illustrated and described embodiment will suggestthemselves, and I accordingly expect that the hereto annexed claims beread with only such limitations as are necessaril introduced thereto todistinguish from prior knowledge in the art.

What I claim is: r

1. In a radial grinding machine, in combination with a grinding tool anda tool mount: a

swingably mounted beam; power devices having operative connection withthe beam for recipalleling the swing aXis of the beam; and mechanismfunctional to the tool mount and operat 'ing automatically in responseto the cyclic swing of the beam to intermittently advance the tool mountupon its support for imparting progressing lead movements to the tool.

2. In a radial grinding machine, in combination with a grinding tool anda tool mount: a

'swingably mounted beam; power devices operative to reciprocally swinthe beam; means provided upon the free end of the beam supporting thetool mount for sliding movement in a direction paralleling the swingingaxis of the beam; and intermittently acting mechanism operatingautomatically in response to the cyclic swing of the beam for advancingthe tool mount progressively upon its support, said mechanism includinga feed-screw functional to the tool mount and a pawl-driven ratchetwheel operative to the feed-screw and itself operated from the swingingmovement of the beam.

3. The combination of claim 2 providing adjustablc stop devices forlimiting the travel of the tool mount upon its slide, and having a fric-"tion-drive connection from the ratchet wheel to the feed-screw actingby slippage to relieve the feed-screw of the driving influence of theratchet wheel. upon a travel of the tool mount to a predetermined endlimit of slide movement.

4. In a radial grinding machine, in combination: a swingably mountedbeam; power devices carriage and having connection with the grindinghead for advancing the latter upon its supfiort; and mechanism operatingautomatically in response to the cyclic swing of the beam for inter--mittently imparting functional movement to the feed-screw.

5. A grinding machine according to claim 4 in which the grinding head isself-contained to provide a grinding tool and an electric motor fordriving the tool movably bodily in relation to the carriage.

6. A grinding machine according to claim 4 in which the power devicesfor reciprocally swinging the beam are comprised of a driving bracketcoupled to the beam and providing a radial extension, a mangle rackhaving radially-adjustable wrist connection with the radial extension,and a motor-driven pinion meshing the teeth of the mangle rack.

7. In a radial grinding machine, in combination: a swingably mountedbeam; power devices operative to impart reciprocatory swinging movementto the beam; a grinding head; a beam carried carriage supporting thegrinding head for sliding movement in a direction paralleling theswinging axis of the beam, and itself supported for sliding movementlongitudinally of the beam; means for manually setting the carriage inrelation to the beam for governing the radial swing for reciprocallyswinging the beam and including a motor-driven drive bracket supportedfor reciprocating movement about an axis coinciding with that of thebeam; a retractible pin for releasably coupling the bracket to the beam;a grinding head slidably supported upon the free end of the beam forsliding movement in a direction paralleling the swinging axis of thebeam; and intermittently acting mechanism operating automatically inresponse to the cyclic swing of the beam for advancing the grinding headprogressively upon its slide.

9. In a radial grinding machine, in combination: a swingably mountedbeam; power devices for reciprocating the beam; a grinding head slidablysupported upon the iree end of the beam for sliding movement in adirection paralleling the swinging of the beam; a feed-screw supportedby the beam and having connection with the grinding head for advancingthe latter upon its support; adjustable stop devices for limiting thetravel of the grinding head upon the slide; a ratchet wheel; meansresponsive to the cyclic swing of the beam for imparting intermittentand uni-directional turning movements to the ratchet wheel; and afriction-drive connection between said ratchet wheel and the feed-screwacting normally to transm t the turning movements of the ratchet wheelto the feed-screw, said connection being operative byresistance-developed slippage to relieve the feed-screw of the drivinginfluence oi the ratchet wheel upon a travel of the grinding head to apredetermined end limit oi slde movement.

30. In a radial grinding machine, in combination: a swingably mountedbeam; power devices in relation to the beam for governing the radialswing of the grinding head; a feed screw carried y the carriage to liein radial relation to the beam and having connection with the grindinghead for advancing the latter progressively upon its support; and meansoperating automatically in response to the cyclic swing of the beam formparting intermittent turning movements to the feed-screw, said meanscomprising a fixedly mounted gear disposed to lie in concentric relationto the swinging axis of the beam, a pinion meshing the teeth of saidgear, a ratchet wheel, a reversible pawl driven from the pinion andoperating to transmit uni-directional turning movements to the ratchetwheel, and connection from the ratchet wheel to the feed-screw forrcsponsively turning the latter.

11. A radial grinding machine according to claim 10, said pinion, theratchet wheel and pawl assembly, and the connection from the ratchetwheel to the feed-screw being mounted directly upon the beam in co-axialrelation to the feedscrew, and wherein the feed-screw is slidablyreeived through the same to compensate for sliding movement of thescrew-supporting carriage longitudinally of the beam.

12. In a radial grinding machine, in combination: a swingably mountedbeam; power devices for reciprocating the beam; a beam-carried grindinghead supported for sliding movement in a direction paralleling theswinging axis of the beam; a feed-screw carried by the beam; connectionfrom the feed-screw to the grinding head functioning to. advance thehead progressively upon its support in response to turning movements ofthe screw; and means including a fixedly mounted sector gear disposedconcentric to the swinging axis of the beam and an intermittentfeedtransmission actuated therefrom in response to cyclic swing of the beamfor turning the screw, said intermittent-feed transmission being carriedby the beam and comprising a pinion meshing the teeth of the sectorgear, a drive disc revoluble with the pinion and provided upon its rimwith peripherally spaced driving dogs, a driven disc provided with aperipheral pick-up lug arranged to lie in the space between and receivea lostmotion drive from the driving dogs, a ratchet wheel, a reversiblepawl carried by the driven disc functioning to transmit uni-directionalturning movements to the ratchet wheel, and connection from the ratchetwheel to the feed-screw for responsively turning the latter.

13. In a radial grinding machine, in combination: a swingably mountedbeam; power devices for reciprocating the beam; mechanism for adjustingthe swinging arc of the beam; a grinding head supported upon the freeend of the beam for sliding movement in a direction paralleling theswinging axis of the beam; a feed-screw carried by the beam; connectionfrom the feed-screw to the grinding head for advancing the latterprogressively upon its support in response to turning movements of thescrew; and means for turning;

the screw in response to cyclic swing of the beam including a fixedlymounted sector gear disposed to lie in concentric relation to theswinging axis of the beam and an intermittent-feed transmission carriedby the beam and actuated from said sector gear, said intermittent-feedtransmission comprising a pinion meshing the teeth of the sector gear, adrive disc revoluble with the pinion and provided upon its rim withperipherally spaced driving dogs, a driven disc provided with aperipheral pick-up lug arranged to lie in the space between and receivea lost-motion drive from the driving dogs, a ratchet wheel, a reversiblepawl carried by the driven disc functioning to transmit uni-directionalturning movements to the ratchet wheel, and connection from the ratchetwheel to the feed-screw for responsively turning the latter.

14. A grinding machine according to claim 3' in which the driving dogsare adjustable peripherally upon the drive disc.

15. In a radial grinding machine, in combination: a swingably mountedbeam; power devices for reciprocating the beam; mechanism for adjustingthe swinging arc of the beam; a carriage mounted for longitudinalsliding movement upon the beam; a grinding head supported by thecarriage for sliding movement in a direction paralleling the swingingaxis of the beam and comprised of a tool-supporting arbor and anelectric motor therefor movable slidably as a unit upon the carriage;means for manually setting the carriage in relation to the beam forgoverning the radial swing of the grinding head; a feedscrew supportedby the carriage; a walking nut threaded upon the screw; connection fromthe walking nut to the grinding head for progressively advancing thelatter upon its support in response to turning movements of the screwand comprised of a bell-crank having link-connection from one of itslever arms to the nut and from the other lever arm to the grinding head;and means for turning the screw in response to the cyclic swing of thebeam including a fixedly mounted sector gear disposed to lie inconcentric relation to the swinging axis of the beam and anintermittent-feed transmission carried by the beam and actuated fromsaid sector gear, said intermittent-feed transmission comprising apinion meshing the teeth of the sector gear, a drive disc revoluble withthe pinion and provided upon its rim with circumferentially spaceddriving dogs, a driven disc provided with a peripheral pick-up lugarranged to lie in the space between and receive a lost-motion drivefrom the driving dogs, a ratchet wheel, a reversible pawlcarried by thedriven disc functioning to transmit unidirectional turning movements tothe ratchet wheel, and connection from the ratchet wheel to thefeed-screw for responsively turning the latter.

16. As a' power-transmitting assembly: the combination of a rotary drivemember arranged and. adapted to be driven in opposite directions ofrotation alternately; a power-transfer wheel; a reversible ratchet drivefrom the drive member to the wheelfor giving intermittentuni-directional movement to the wheel in either direction of rotation,selectively; a rotary driven member; stop means for positively limitingthe rotational movement of said driven member; and a friction drive fromthe wheel to the driven member for driving the latter through thepermitted range of the driven members movement, the cessation ofmovement of the driven member upon the exercise of said stoppingfunction of the stop means causing slippage in the friction drivebetween said wheel and the driven member.

' WILLIAM L. CARSON.

